A. Technical Field
The present invention relates to a post frame for X-ray apparatus and in particular a post frame provided on a ceiling type X-ray apparatus that reduces cost and provides a simple installation and durability.
The present invention also relates to a ceiling type X-ray apparatus that has the post frame, reduces a tension load difference of the spring balancer and prevents an accident.
B. Background of the Invention
In general, X-ray apparatus is used to carry out a visual inspection of internal diseases, in particular analyze whether there is any damage at a chest, a head, a digestive canal, a spine, or any other injured part by X-ray radiation.
Medical diagnosis device used in a hospital is configured to such that X-ray radiated from the X-ray tube penetrates an object to be examined such as a body of animal or human to detect the object.
Prior X-ray apparatus is shown in FIG. 1 which is a ceiling type X-ray apparatus 1. The ceiling type X-ray apparatus is configured to take a photo when an examinee lies on the table between an X-ray tube and an X-ray film. In this apparatus, a guide rail is installed on the ceiling of the examination room, a post frame 10 is foldably connected to a support that moves along the guide rail, and an X-ray tube 2 is provided on the bottom of the post frame.
To make the post frame 10 foldable, the post frame 10 is received in a fixed member fixed to the support, and the post frame 10 comprises a main body that consists of a plurality of movable member 11 that moves upward and downward along the length of the fixed member.
In the ceiling type X-ray apparatus 1, as shown in FIG. 2(a), a guide block 30a is formed by material that has a high durability and wear-resistance by the heat-treatment because the guide block is subject to deterioration or degradation by the frictional contact with the bearing when it moves upward and downward.
In the above post frame that moves upward and downward, the guide block is manufactured separately and then is fixed to the fixed frame or movable member of the post frame by welding, etc. Therefore, the complex process for manufacturing the post frame increases the manufacture time and cost.
Moreover, in the conventional post frame structure, since the guide block 30 is in surface contact with the bearing, a friction increases and a lot of energy is required to move X-ray apparatus upward and downward. Due to the non-uniform surface-contact with the bearing 21, a spring balancer (not shown) is further provided in the main body 11 and the bearing 21 is pressed against the guide block 30 by the elastic force of the spring balancer.
Further, when the post frame rotates to take a photo of an examinee, the guide block 30 having a box-shape causes torsion and noise. Since the bearing 21 and the guide block 30 have a weak wear resistance, they are liable to be broken. When broken, the whole main body 11 has to be replaced and therefore the cost increases.
To solve the above problem, the side of the guide block 30 that is in contact with the bearing 21 can be rounded as shown in FIG. 2(b). However, the rounding of the side of the guide block 30 increases a manufacturing time and cost.
Meanwhile, a prior ceiling type X-ray apparatus has a problem that the tension load difference of the spring balancer is high for the travel section of the post frame. The longer the travel section of the post frame, i.e., the travel length of the X-ray tube, is the more springs are wound on the spring balancer. Assuming the travel length of the X-ray tube is 1,500 mm, the difference in the tension load of the spring balancer between the starting point of the travel length and the end point of the travel length is substantial. The difference in the spring tension exerts substantial load on the X-ray apparatus. This results in a deterioration or degradation and in turn requires much energy to operate the apparatus.
To solve the above problem, the inventor has designed a ceiling type X-ray apparatus to reduce a load of the apparatus as shown in FIG. 3. This apparatus comprises a wire drum 31; a wire taper drum 32 arranged coaxially with the wire drum and having a plurality of steps on which wire is wound; and an acceleration drum 33 on which a wire from the wire taper drum is wound and which has a diameter smaller than that of the spring drum, wherein the wire drum consists of a plurality of wire drums having different diameter, and wherein a wire wound on the wire drum having a smaller diameter is connected to the spring balancer, thereby reducing the tension load difference between the starting point and the end point of the spring balancer even for the long travel length of X-ray tube.
However, the ceiling X-ray apparatus is provided with only one line of wire that is wound on the wire taper drum. The destruction of the wire causes a non-working of the apparatus and an accident.
To solve the above problems, the present invention provides a post frame for X-ray apparatus that reduces a manufacturing time and cost by improving a structure for raising and lowering the post frame and that reduces an energy for operating the apparatus by reducing the friction between a bearing and a guide block.
Another object of the present invention is to provide an adjustable length post frame for X-ray apparatus that reduces torsion or noise during the movement or rotation of the post frame and reduces cost by increasing durability.
Another object of the present invention is to reduce a load exerted on X-ray apparatus by reducing the difference in tension load between the starting point and the end point for the long travel length of X-ray tube, to save energy required to operate the apparatus and to prevent a stop of the apparatus and an accident when wire is cut.